A North Korean soldier's bold attempt to defect by crossing the heavily guarded border with South Korea galvanized attention this week.

But perhaps more surprising was the disclosure by surgeons struggling to save his life of what they found while repairing his intestinal wounds: dozens of parasitic worms, some as long as 11 inches.

"In my 20 years as a surgeon, I have only seen something like this in a medical textbook," said Dr. Lee Cook-jong, a lead surgeon.

The discovery opened a window on the dire conditions in North Korea, including poor hygiene and nutrition. The news shocked many people in prosperous South Korea.

Surgeons raced to save the North Korean soldier, whose name and rank have not been released, who sustained serious bullet wounds racing across the border while his own troops fired on him.

"We have found dozens of fully grown parasitic worms in his damaged intestines,' said Dr. Lee Cook-jong, a lead surgeon.

"It was a serious parasitic infection."

During a news briefing this week, Dr. Lee showed photographs of worms as long as 10 or 11 inches.

Experts in parasitic worms were not surprised, however. They said that the finding was consistent with the broad sense of conditions in the isolated, impoverished North.

Defectors to the South have cited the existence of parasites and abysmal nutrition. Because it lacks chemical fertilizers, North Korea still relies on human excrement to fertilize its fields, helping parasites to spread, the experts said.

In a 2014 study, South Korean doctors checked a sample of 17 female defectors from North Korea and found seven of them infected with parasitic worms.

The North Korean soldier drove a jeep into the Joint Security Area, one of the most heavily guarded portions of the Demilitarized Zone, on Monday. He then ran across the border to defect to the South while fellow North Korean troops unleashed a hail of rifle and pistol shots trying to stop him.

He collapsed about 55 yards south of the border, bleeding profusely. South Korean officers pulled him to safety, and a United States Black Hawk military helicopter rushed him to a hospital near Seoul, where he underwent a series of surgeries.

His was the most dramatic defection from the North in years, making headlines in South Korea.

But more startling news came from the doctors who were working to clean and patch up his dietary tract, which was torn by bullets.

The soldier's condition was particularly noteworthy because North Korean soldiers, especially those deployed near the border with South Korea, receive priority in food rationing. Yet, in addition to the parasitic worms, doctors found kernels of corn in his stomach.

South Korea itself was afflicted with widespread parasitic infections through the 1970s, when more than 80 percent of the population carried parasitic worms. After a 9-year-old girl died in 1963 and doctors found more than 1,000 parasitic worms in her body, the country launched a national campaign to eradicate parasites.

Schools collected stool samples from students and distributed anti-parasitic pills. The campaign succeeded: Parasitic infections have become rare in South Korea as hygiene and economic conditions have improved.

More than 30,000 North Koreans have fled to South Korea since a famine killed more than a million people in the North in the 1990s. Since then, international relief agencies have reported widespread malnutrition and stunted growth among many children in the North.

The wounded soldier, who is believed to be in his late 20s, is 5 feet 5 inches tall and weighs 132 pounds. In contrast, an average high school male senior in South Korea is 5 feet 8 inches tall and weighs 154 pounds.

Not a used car, a piece of land, or an item of furniture. Not "merchandise" at all, but two human beings.

One of the unidentified men being sold in the grainy cell phone video obtained by CNN is Nigerian. He appears to be in his twenties and is wearing a pale shirt and sweatpants.

He has been offered up for sale as one of a group of "big strong boys for farm work," according to the auctioneer, who remains off camera. Only his hand -- resting proprietorially on the man's shoulder -- is visible in the brief clip.

After seeing footage of this slave auction, CNN worked to verify its authenticity and traveled to Libya to investigate further.

Carrying concealed cameras into a property outside the capital of Tripoli last month, we witness a dozen people go "under the hammer" in the space of six or seven minutes.

"Does anybody need a digger? This is a digger, a big strong man, he'll dig," the salesman, dressed in camouflage gear, says. "What am I bid, what am I bid?"

Buyers raise their hands as the price rises, "500, 550, 600, 650 ..." Within minutes it is all over and the men, utterly resigned to their fate, are being handed over to their new "masters."

After the auction, we met two of the men who had been sold. They were so traumatized by what they'd been through that they could not speak, and so scared that they were suspicious of everyone they met.

Each year, tens of thousands of people pour across Libya's borders. They're refugees fleeing conflict or economic migrants in search of better opportunities in Europe.

Most have sold everything they own to finance the journey through Libya to the coast and the gateway to the Mediterranean.

But a recent clampdown by the Libyan coastguard means fewer boats are making it out to sea, leaving the smugglers with a backlog of would-be passengers on their hands.

So the smugglers become masters, the migrants and refugees become slaves.

The evidence filmed by CNN has now been handed over to the Libyan authorities, who have promised to launch an investigation.

First Lieutenant Naser Hazam of the government's Anti-Illegal Immigration Agency in Tripoli told CNN that although he had not witnessed a slave auction, he acknowledged that organized gangs are operating smuggling rings in the country.

"They fill a boat with 100 people, those people may or may not make it," Hazam says. "(The smuggler) does not care as long as he gets the money, and the migrant may get to Europe or die at sea."

"The situation is dire," Mohammed Abdiker, the director of operation and emergencies for the International Organization for Migration, said in a statement after returning from Tripoli in April. "Some reports are truly horrifying and the latest reports of 'slave markets' for migrants can be added to a long list of outrages."

The auctions take place in a seemingly normal town in Libya filled with people leading regular lives. Children play in the street; people go to work, talk to friends and cook dinners for their families.

But inside the slave auctions it's like we've stepped back in time. The only thing missing is the shackles around the migrants' wrists and ankles.

Anes Alazabi is a supervisor at a detention center in Tripoli for migrants that are due to be deported. He says he's heard "a lot of stories" about the abuse carried out by smugglers.

"I'm suffering for them. What I have seen here daily, believe me, it makes me feel pain for them," he says. "Every day I can hear a new story from people. You have to listen to all of them. It's their right to deliver their voices."

One of the detained migrants, a young man named Victory, says he was sold at a slave auction.

Tired of the rampant corruption in Nigeria's Edo state, the 21-year-old fled home and spent a year and four months -- and his life savings -- trying to reach Europe.

He made it as far as Libya, where he says he and other would-be migrants were held in grim living conditions, deprived of food, abused and mistreated by their captors.

"If you look at most of the people here, if you check your bodies, you see the marks. They are beaten, mutilated."

When his funds ran out, Victory was sold as a day laborer by his smugglers, who told him that the profit made from the transactions would serve to reduce his debt. But after weeks of being forced to work, Victory was told the money he'd been bought for wasn't enough. He was returned to his smugglers, only to be re-sold several more times.

The smugglers also demanded ransom payments from Victory's family before eventually releasing him.

"I spent a million-plus [Nigerian naira, or $2,780]," he tells CNN from the detention center, where he is waiting to be sent back to Nigeria. "My mother even went to a couple villages, borrowing money from different couriers to save my life."

As the route through north Africa becomes increasingly fraught, many migrants have relinquished their dreams of ever reaching European shores. This year, more than 8,800 individuals have opted to voluntarily return home on repatriation flights organized by the IOM.

While many of his friends from Nigeria have made it to Europe, Victory is resigned to returning home empty-handed.

"I could not make it, but I thank God for the life of those that make it," he says.

"I'm not happy," he adds. "I go back and start back from square one. It's very painful. Very painful."

"Amina J. Mohammed, the U.N. deputy secretary-general, has ascended to the lofty pinnacle of global diplomacy on the back of her record as a champion of the environment and the poor. But in January, just weeks before assuming her current job, she spent her final days as Nigeria's environment minister doing something that has outraged activists. Despite a ban then in force on the export of rosewood, an endangered resource, she signed thousands of certificates authorizing the shipment of vast quantities of the wood.

The certificates 'came in bags, and I just signed them because that is what I had to do,' she recalled in an interview last month in her sprawling 38th-floor U.N. headquarters office in Manhattan overlooking the East River. 'I don't remember how many.'...

Mohammed's 11th-hour decision to approve the kosso shipments was first documented by a Washington-based environmental group and is now part of an inquiry by the secretariat of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), to which Nigeria is a signatory...

The thousands of 'hand-signed permits violate both Nigeria's export ban' and provisions of the endangered species treaty, Alexander von Bismarck, the executive director of EIA, claimed in an interview with FP. 'More importantly, the laundering of Nigerian rosewood decimates millions of hectares of fragile forest and imperils the lives of millions of people.'..."